The present invention relates to a semiconductor device and a method of manufacturing the same. Particularly, the present invention is concerned with a technique applicable effectively to the manufacture of a semiconductor device in which a semiconductor chip having a power transistor is sealed.
As a high output semiconductor device there is known a semiconductor device wherein a semiconductor chip having a power transistor such as, for example, a power MOSFET (Metal Oxide Semiconductor Field-Effect-Transistor), an IGBT (Insulated Gate Bipolar Transistor), or a bipolar power transistor is incorporated into a sealing member.
A power MOSFET device has a structure wherein a power MOSFET chip is incorporated into a sealing member. As a power MOSFET device there is known one having a structure wherein metallic members serving as drain terminals are exposed to the bottom of a sealing member formed of an insulating resin and a lead terminal for source and a lead terminal for gate are disposed on one side of the sealing member. The lead terminal for source and the lead terminal for gate are partially bent and exposed to an upper surface of the sealing member. Both lead terminals for source and gate are electrically connected respectively to a source electrode and a gate electrode on an upper surface of a semiconductor chip which is fixed onto the metallic member. These leads are ultrasonic compression-bonded to gold (Au) bumps which are arranged uniformly on the source and gate electrodes by a ball bonding method. (See, for example, Patent Literature 1.)
On the other hand, in connection with a method of manufacturing a power MOSFET of the same structure, there also is known a technique wherein gold bumps are formed at the stage of a semiconductor wafer and thereafter the semiconductor wafer is diced to form semiconductor chips each having gold bumps (see, for example, Patent Literature 2).
[Patent Literature 1]
Japanese Patent Application Laid-Open No. 2000-223634 (page 7, FIGS. 1 and 17)
[Patent Literature 2]
Japanese Patent Application Laid-Open No. 2003-86787(page 4, FIG. 1)